ISO 22190-2020 pdf free.Soil quality — Use of extracts for theassessment of bioavailability of traceelements in soils.
1.Scope:This document provides guidance on the use of chemical methods establishing the bioavailability oftrace elements in soil and soil-like materials and to stimulate the use of bioavailability in assessments.The methods themselves are not subject of this document.
2.Normative references:The following documents are referred to in the text in such a way that some or all of their contentconstitutes requirements of this document. For dated references,only the edition cited applies.Forundated references, the latest edition of the referenced document(including any amendments) applies.
3.1.bioavailability:degree to which chemicals present in the soil can be absorbed or metabolised by a human or ecologicalreceptor or are available for interaction with biological systems.Note 1 to entry: The concept of bioavailability is further explained in IS0 17402.
Note 2 to entry: This document follows the approach of Reference [20 as illustrated in Figure 2, in which alldefined fractions are measurable as further explained in Clause 4.Note 3 to entry: In ISO 17924 a definition specific for human uptake through ingestion is defined as the fractionof a substance present in ingested soil that reaches the systemic circulation (blood stream).
[SOURCE:ISO 11074:2015,5.2.2, modified—Note 2 to entry was added and the following note to entryrenumbered.]
3.2.environmental availability:fraction of contaminant physico-chemically driven by desorption processes potentially available toorganisms.
3.3.environmental bioavailability:fraction of the environmentally available compound which an organism takes up through physiologicallydriven processes
[SOURCE: ISO 17402:2008,3.5]
3.4toxicological bioavailability:internal concentration of pollutant accumulated and/or related to a toxic effect
3.5.actual availability:concentration present in the soil pore water to which organisms are directly exposed.
Note 1 to entry: This definition refers to internal concentrations in humans,mammals and other organisms.[SOURCE: ISO 17402:2008,3.18]
3.6.potential availability:amount present in the soil sample (mg/kg) that can be released from the solid phase to the pore waterwithin a specific time frame.Because the total exposure of organisms depends on time, the available fraction is not a fixed fraction,but should be divided into multiple fractions or be described as a continuum. The release of thecontaminants depends on local environmental conditions (e.g. pH).The simplest approach determines:a) an actually available fraction or the actual dissolved amount at ambient conditions;
b) a potentially available fraction, which is the maximum amount that can be released to the soil pore water under (predefined) worst-case conditions. This can also be expressed as the reactivefraction;ISO 22190 pdf download.